Having discarded a key idea about his work on Black Holes - that they can lock away the past forever - Stephen Hawking is hard at work on a theory about everything, or more precisely a theory about a theory about everything. Because one key lesson of quantum theory is that the constituents of reality have many possible futures, the latest issue of Discover says that Hawking
is now pushing a different strategy, which he calls top-down cosmology. It is not the case, he says, that the past uniquely determines the present. Because the universe has many histories and just as many possible beginnings, the present state of the universe selects the past. 'This means the the histories of the Universe depend on what is being measured,' Hawking wrote in a recent paper, 'contrary to the usual idea that the Universe has an objective, observer-independent history.'
I'm guessing that author and columnist for Astronomy magazine, Bob Berman, might have something to say about this at IdeaFestival 2009. You are coming aren't you?
Wayne
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